diff --git a/tools/sandbox/config.php b/tools/sandbox/config.php
index 272cb22d6..b60f0eb36 100644
--- a/tools/sandbox/config.php
+++ b/tools/sandbox/config.php
@@ -7,7 +7,8 @@ $classLoader->setBasePath('Doctrine', realpath(__DIR__ . '/../../lib'));
 $classLoader->setBasePath('Entities', __DIR__);
 
 $config = new \Doctrine\ORM\Configuration;
-$cache = new \Doctrine\Common\Cache\ApcCache;
+$cache = new \Doctrine\Common\Cache\ArrayCache;
+// $cache = new \Doctrine\Common\Cache\ApcCache; # RECOMMENDED FOR PRODUCTION
 $config->setMetadataCacheImpl($cache);
 $config->setQueryCacheImpl($cache);
 
diff --git a/tools/sandbox/index.php b/tools/sandbox/index.php
index 3ffbe8677..58d30bbdb 100644
--- a/tools/sandbox/index.php
+++ b/tools/sandbox/index.php
@@ -2,4 +2,4 @@
 
 require 'config.php';
 
-// Place your code here. $em is at your service.
\ No newline at end of file
+// Place your code here. $em is at your service.